Energy-Efficient and Environmentally Advanced Configurations for Naphtha Hydrotreating Process

ABSTRACT

Systems and methods of hydrotreating different naphtha feed stocks destined for a refining reforming unit and other applications with less energy consumption than conventionally possible, while producing less greenhouse gas emissions, and/or using a lesser number of heaters and correspondingly less capital investment in such heaters, air coolers, and water coolers, are provided. According to the more examples of such systems and methods, such reductions are accomplished by directly integrating a naphtha stripping process section with a naphtha splitting process section. Additional reductions can also be accomplished through directly integrating a naphtha hydrotreat reaction process section with the naphtha stripping process section.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a divisional of and claims priority to U.S. patentapplication Ser. No. 13/099,144 titled “Energy-Efficient andEnvironmentally Advanced Configurations for Naptha HydrotreatingProcess” and filed on May 2, 2011

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to the field of naphthahydrotreating processes, and in particular, to systems and methodsrelated to waste heat recovery for naphtha hydrotreating (NHT) processesfor the desulfurization of naphtha.

2. Description of the Related Art

A petroleum refinery generally includes multiple separate unitoperations and processes. One of the operations/processes includes thecontinuous distillation of petroleum to form a liquid distillate callednaphtha which forms a major component of the refineries' product. Afterextraction through distillation, naphtha is generally further processedin catalytic reforming units, such as continuous catalyst circulationreactor (CCR) units, which require a certain naphtha feedstockspecification to avoid degradation in the catalyst performance andreduced life of the downstream units. The naphtha and other distillates,however, in their initial form include numerous undesirable materialssuch as sulfur, nitrogen, olefins, and aromatics. In order to preventdamage to such units and to comply with new stringent environmentallaws, worldwide, the distillates are subjected to a naphthahydrotreating (NHT) process to remove the undesirable materials.

The naphtha hydrotreating process for removing such undesirablematerials is one of the most mature process technologies in the oilrefining processes and its use has become the norm in both old and newrefineries. In the fifties of the last century, companies started tolicense naphtha hydrotreating processes under names such as “Unifining”;“Unionfining”, and other processes. Since then, the process has gonethrough many changes.

The naphtha hydrotreating process functions to remove the undesirablematerials (e.g., sulfur, nitrogen, metals) from the petroleumdistillates by selectively having these materials react with hydrogen ina catalyst bed at elevated temperature in a reactor unit. The chemistrybehind the naphtha hydrotreating process can be divided into a number ofreaction categories, called hydro-desulfurization,hydro-denitrification, saturation of olefins, and saturation ofaromatics. For each of these reactions, hydrogen is normally used toachieve the desired quality of the petroleum fraction.

Desulfurization is by far the most common of the naphtha hydrotreatingreactions. The content and form of the sulfur in hydrocarbons can vary.The reaction rates for different forms of sulfur can also varysignificantly. For example, a Thiophenol reaction that results inbenzene and hydrogen sulfide (H2S) is typically very rapid.

The degree at which sulfur can be removed from the hydrocarbons can varyfrom one petroleum distillate to another. In naphtha, however, sulfurremoval can reach to near complete. Regardless of the content, form, orreaction rate, the desulfurization reaction results in the production ofH2S in the reactor. To complete the desulfurization process, such H2S isremoved in a downstream fractionation unit.

A main use of the naphtha hydrotreating process in naphtha applicationsis in the preparation of feed stocks provided to a naphtha reformingunit. A typical hydrotreating process includes a reactor section, astripper section, and a naphtha splitter section. The reaction sectionprovides hydrogenation, desulfurization, denitrogenation reactions on ahydrotreatment catalyst. In the reaction section, hydrogen is combinedwith the feed and the stream is heated up to the desired hydrotreatingtemperature using a fired heater. The combined feed and hydrogen streampasses downward in a hydrogenation reactor packed with various types ofcatalyst depending upon reactions desired. The reactor effluent iscooled and a liquid phase from the cooled effluent is sent to thecontaminants stripping section. This cooled effluent from the reactionsection is preheated, usually against the stripper bottom product streamand then sent to the stripping column. The stripper effluent is cooledand enters the high pressure separator which separates the liquidhydrocarbon from the hydrogen/hydrogen sulfide/ammonia gas. The acidgases are absorbed from the hydrogen in an amine absorber, and hydrogen,minus purges, is recycled with make-up hydrogen. The stripper bottomproduct provides the “feed” to a naphtha splitter section. This “feed”is first preheated against the splitter bottom stream and sent to thesplitter section. In the splitter section, light naphtha is separatedfrom heavy naphtha, which is used as “feed” by a continuous catalystregeneration and reforming unit (CCR) to produce high octane components.The naphtha hydrotreating process reduces the sulfur and nitrogen in thefeedstock to the downstream catalytic reforming process unit to lessthan 0.5 wt ppm and the metals to non-detectable levels.

Most of the old and recently built naphtha hydrotreating plants useeither Axens or UOP processes. These two conventional configurations arealmost the same with respect to the configuration of the contaminantsstripper and naphtha splitter sections. Recognized by the inventors isthat neither configuration exhibits direct integration between the twosections.

Waste heat recovery has been employed in conventional naphthahydrotreating processes, including in these exemplary processes, inorder to reduce the amount of energy consumed. In such processes, thefeed to the respect to section is typically preheated by the bottomproduct of the section and the extra waste heat in the heavy naphthastream from the naphtha splitter section is sent to the air and watercoolers.

Although very simple, the contaminants stripper and a naphtha splittersections however, use huge amounts of heating utilities, most of thetime in the form of fossil fuel consumed in re-firing units assigned toeach of the sections. These fired heaters, used to supply the requiredheating utility, also produce a large quantity of undesirable emissions.In some parts of the world, such emissions are catastrophic to theenvironment. As noted above, the stripper and splitter sections alsorequire huge cooling utilities in form of air coolers and water coolers.Air coolers are capital and maintenance intensive equipment and watercooling, and in some parts of the world have significant availabilityand maintenance problems, as well.

Recognized by the inventors is that, even in view of such difficultiessurrounding the use of external utilities, such conventional energyrecovery methods fail to optimize waste heat recovery within and betweenthe processes. Accordingly, the inventors have recognized that it wouldbe beneficial to the oil refining industry to hydrotreat differentcategories/types of naphtha feed stocks destined for a refiningreforming unit and other applications with less energy consumption thanconventionally possible, while producing less green house gas emissions,and/or using a lesser number of heaters and correspondingly less capitalinvestment in such heaters, air coolers, and water coolers.

Particularly, recognized by the inventors is that it would be beneficialto the oil refining industry to hydrotreat different naphtha feed stocksdestined for a refining reforming unit with less energy consumption by(destined for) fired heaters and with less energy consumption by airand/or water coolers, while producing less green house gas emissions.Further, recognized by the inventors is that it would be beneficial tothe oil refining industry to hydrotreat the naphtha feed stocks destinedfor a refining reforming unit using a lesser number of heaters and usingless capital investment in plant's heaters, air and water coolers. Stillfurther, recognized by the inventors is that it would be beneficial tothe oil refining industry to hydrotreat the naphtha feed stocks destinedfor refining reforming unit using a process configuration that can beused worldwide in any naphtha hydrotreating process including in placeswith extreme differences in energy cost. Additionally, it would be alsovery beneficial to have a naphtha hydrotreating process reaction furnacethat is flexible and with a low beta ratio to handle different feedstocks. It would also be extremely beneficial to the refining industryto have a naphtha hydrotreating process configuration with an efficientwaste heat recovery system that is retrofitable for more efficientenergy usage along the lifetime of the naphtha hydrotreating plant.

SUMMARY OF THE INVENTION

In view of the foregoing, various embodiments of the present inventionadvantageously provide systems and methods of hydrotreating differentnaphtha feed stocks destined for a refining reforming unit and otherapplications with less energy consumption (e.g. in fired heaters and/orair and/or water coolers) than conventionally possible, while producingless green house gas emissions, and/or using a lesser number of heatersand correspondingly less capital investment in such heaters, aircoolers, and water coolers than conventionally done. Various embodimentsof the present invention advantageously provide systems and methods ofhydrotreating different naphtha feed stocks for the desulfurization ofnaphtha destined for a refining reforming unit that is retrofitable formore efficient energy usage along the lifetime of the naphthahydrotreating plant. Various embodiments of the present inventionadvantageously provide systems and methods of hydrotreating differentnaphtha feed stocks destined for a refining reforming unit using aprocess configuration that can be used worldwide in any naphthahydrotreating process including in places with extreme differences inenergy cost. Various embodiments of the present invention advantageouslyprovide a naphtha hydrotreating process reaction furnace that isflexible and with a low beta ratio in the reaction section to handledifferent feed stocks.

Advantageously, various embodiments of the present invention achieve theabove advantages/objectives through the direct integration between thestripping and naphtha splitting sections and/or between the reaction,stripping, and naphtha splitting sections, to significantly reduce boththe heating and cooling utilities consumption of existing and newprocesses by at least 20% and 60% respectively, and its associatedenergy-based emissions by more than million ton of CO2 along thelifetime of the plant.

More specifically, an example of an embodiment of a method of providinghydrotreated naphtha feedstocks to a refining reforming unit includesthe step of directly integrating a naphtha stripping process sectionwith a naphtha splitting process section. The step of directlyintegrating can include providing a reboiling process-to-process heatexchanger unit receiving a bottom stream product of heavy naphtha from anaphtha splitter and a bottom stream product from a naphtha stripper totransfer heat from the bottom stream product from the naphtha stripperto the bottom stream product from the naphtha splitter. The steps ofdirectly integrating can also include providing a fired heater unitoperably connected in line with and downstream of the reboilingprocess-to-process heat exchanger to provide additional heat to thebottom stream product from the naphtha splitter to reboil bottom streamproduct from naphtha splitter, and conducting reboiling of the heavynaphtha bottom stream product from the naphtha splitter utilizing thenaphtha stripper bottom stream product from the naphtha stripper inconjunction with the fired heater unit.

The step of directly integrating can also include providing ahigh-heat-transfer capacity process-to-process heat exchanger receivingbottom stream product of heavy naphtha from the naphtha splitter(reforming feed to a refining reforming unit) and reactor product from areactor unit of a reaction process section to aggressively cool theheavy naphtha bottom stream product from the naphtha splitter to lessthan approximately 200° F., and more preferably down to a temperature ofapproximately 173° F. Beneficially, such configuration can facilitatefurther downstream cooling of the heavy naphtha bottom stream productusing an air cooler positioned to receive a heavy naphtha bottom streamproduct feed from the naphtha splitter, to an extent that thecombination of high-heat-transfer capacity process-to-process heatexchanger and air cooler is sufficient to negate a need for anon-air-cooled chilling unit.

Another example of an embodiment of a method of providing hydrotreatednaphtha feedstocks to a refining reforming unit includes the step ofdirectly integrating a naphtha stripping process section with a naphthasplitting process section. According to this exemplary embodiment of themethod, the step of directly integrating includes providing a firstreboiling process-to-process heat exchanger unit receiving a bottomstream product of heavy naphtha from a naphtha splitter and a bottomstream product from a naphtha stripper to transfer heat from the bottomstream product from the naphtha stripper to the bottom stream productfrom the naphtha splitter, and providing a second reboiling heatexchanger unit operably receiving additional bottom stream product fromthe naphtha stripper and additional bottom stream product from thenaphtha splitter so that the additional bottom stream product from thenaphtha stripper provides heat energy to the additional bottom streamproduct from the naphtha splitter to reboil the additional bottom streamproduct from the naphtha splitter. The step of directly integrating canalso include providing a fired heater unit operably connected in linewith and downstream of the second process-to-process heat exchanger toreboil bottom stream product from naphtha stripper to replenish heattransferred to the bottom stream product from the naphtha stripper tobottom stream product from the naphtha splitter and to add additionalheat thereto sufficient for reboiling.

The direct integration also includes conducting reboiling of the heavynaphtha bottom stream product from the naphtha splitter utilizing boththe first reboiling process-to-process heat exchanger unit (receivingheat from the naphtha stripper bottom stream product providing feed tothe naphtha splitter) and the second reboiling process-to-process heatexchanger unit (receiving heat from the naphtha stripper bottom streamproduct enroute to the fired heater unit). Beneficially, according tothis exemplary configuration, the first and the second reboilingprocess-to-process heat exchanger units are collectively configured toprovide sufficient heat exchange capacity to reboil the bottom streamproduct from the naphtha splitter without use of a fired heater unitpositioned to directly reboil the bottom stream product from naphthasplitter. That is, in the exemplary configuration, the naphtha splittingprocess section is devoid of a fired heater unit.

Another example of an embodiment of a method of providing hydrotreatednaphtha feedstocks to a refining reforming unit also includes the stepof directly integrating a naphtha stripping process section with anaphtha splitting process section, and directly integrating a naphthahydrotreat reaction process section with the naphtha stripping processsection. The step of directly integrating the naphtha stripping processsection with the naphtha splitting process section can include providinga first reboiling process-to-process heat exchanger unit receiving abottom stream product of heavy naphtha from a naphtha splitter and abottom stream product from a naphtha stripper to transfer heat from thebottom stream product from the naphtha stripper to bottom stream productfrom the naphtha splitter. The step of directly integrating the naphthastripping process section with the naphtha splitting process section canalso include providing a fired heater unit operably connected in linewith and downstream of the first process-to-process heat exchanger toprovide additional heat to the bottom stream product from the naphthasplitter to reboil bottom stream product from naphtha splitter, andconducting reboiling of heavy naphtha bottom stream product from thenaphtha splitter utilizing the naphtha stripper bottom stream productfrom the naphtha stripper in conjunction with the fired heater unit.

The step of directly integrating the naphtha hydrotreat reaction processsection with the naphtha stripping process section can include providinga second reboiling process-to-process heat exchanger unit receivingbottom stream product from the reactor unit and the bottom streamproduct from the naphtha stripper so that the bottom stream product fromthe reactor unit provides heat energy to the bottom stream product fromthe naphtha stripper. The step of directly integrating the naphthahydrotreat reaction process section with the naphtha stripping processsection can also include conducting reboiling of the naphtha stripperbottom stream product received from the naphtha stripper by the secondreboiling process-to-process heat exchanger unit through use of thereactor unit bottom stream product received from the reactor unit.

According to one or more additional configurations, the step ofproviding the second reboiling process-to-process heat exchanger unitcan include increasing the surface area of the heat exchanger unitand/or increasing the flow rate of the bottom stream product from thereactor unit and/or the flow rate of the bottom stream product from thenaphtha stripper as necessary to reduce the amount of heating utilityrequired for reboiling the stripper bottom stream product. Notably, theparameter adjustments can be made up to an extent of providingsufficient heat exchange capacity to reboil the bottom stream productfrom the naphtha stripper without use of a fired heater unit positionedto directly reboil the bottom stream product from naphtha stripper. Thisbeneficially can allow the naphtha stripping process section to bedevoid of a fired heater.

Various embodiment of the present invention also include systems tohydrotreat naphtha feedstocks for provision to a refining reformingunit. According to an example of an embodiment of such a system, thesystem can include a naphtha splitting process section including anaphtha splitter providing heavy naphtha bottom stream product to arefining reforming unit as feed, a naphtha stripping process sectionincluding a naphtha stripper providing bottom stream product to thenaphtha splitter as feed, and a naphtha hydrotreat reaction processsection including a reactor unit providing bottom stream product to thenaphtha stripper as feed.

The system can also include a first process-to-process heat exchangerunit positioned to receive bottom stream product from the naphthastripper and bottom stream product of heavy naphtha from the naphthasplitter so that the bottom stream product from the naphtha stripperprovides heat energy to the bottom stream product from the naphthasplitter. A first conduit is operably connected between a bottom streamproduct outlet port of the naphtha stripper and a first inlet port inthe heat exchanger unit. A second conduit is operably connected betweena first outlet port of the heat exchanger unit and a naphtha stripperbottom stream product receiving inlet port in the naphtha splitter, withthe second conduit being in fluid communication with the first conduitthrough the heat exchanger unit. A third conduit is operably connectedbetween a bottom stream product outlet port of the naphtha splitter anda second inlet port in the heat exchanger unit. A fourth conduit isoperably connected between a second outlet port of the heat exchangerunit and a reboiling inlet port in the naphtha splitter, with the fourthconduit being in fluid communication with the third conduit through theheat exchanger unit.

According to this exemplary configuration, the naphtha splitter, thenaphtha stripper, and the heat exchanger unit are operably coupled sothat when operationally employed the bottom stream product from thenaphtha stripper flowing through the first and the second conduits andassociated portions of the heat exchanger unit is in thermalcommunication with the bottom stream product from the naphtha splitterflowing through the third and the fourth conduits and associatedportions of the heat exchanger unit to thereby conduct reboiling of thenaphtha bottom stream product from the naphtha splitter through use ofthe bottom stream product from the naphtha stripper.

The system can also include a high-heat-transfer capacity secondprocess-to-process heat exchanger unit positioned to receive condensedportions of bottom stream product from the reactor unit and the bottomstream product from the naphtha splitter so that the condensed portionsof the bottom stream product from the reactor unit extracts substantialheat energy from the bottom stream product from the naphtha splitter. Aconduit is operably connected between a bottom stream product outletport in the reactor unit and a first inlet port in the second heatexchanger unit. Another conduit is operably connected between a firstoutlet port of the second heat exchanger unit and a naphtha feed inletport in the naphtha stripper, with this conduit being in fluidcommunication through the second heat exchanger unit with the conduitconnected to the first inlet port. Another conduit is operably connectedbetween a bottom stream product outlet port in the naphtha splitter anda second inlet port in the second heat exchanger unit, and an associatedconduit is operably connected between a second outlet port of the secondheat exchanger unit and hydrotreated product feed inlet port in acatalytic reformer unit, with this conduit being in fluid communicationthrough the second heat exchanger unit with the conduit connected to thesecond inlet port.

Similar to the prior described embodiment, according to anotherembodiment of a system, the reactor unit, the naphtha stripper, and asecond heat exchanger unit are operably coupled so that whenoperationally employed, the bottom stream product from the reactor unitflowing through a respective one of the pairs of conduits and associatedportions of the second heat exchanger unit, is in thermal communicationwith the bottom stream product from the naphtha splitter flowing throughthe other pair of conduits and associated portions of the second heatexchanger unit to thereby cool the bottom stream product from thenaphtha splitter through use of the bottom stream product from thereactor unit. Beneficially, such cooling can be sufficient to negate aneed for a non-air cooled chilling unit to be employed between thesecond outlet port of the second heat exchanger and the hydrotreatedproduct feed inlet port in a catalytic reformer unit.

Accordingly, in this exemplary configuration, the system is devoid ofany non-air cooled chilling units associated with the reforming feed.Rather, the system can include an air cooler operably coupled to thesecond heat exchanger unit and the catalytic reformer unit to receivethe heavy naphtha bottom stream product from the naphtha splitter and toprovide cooled bottom stream product from the naphtha splitter(reforming feed) to the catalytic reformer unit. Notably, suchconfiguration allows for a temperature of the heavy naphtha bottomstream product provided to the catalytic reformer unit to be less than200° F., and more typically 173° F., even without use of any non-aircooled chilling units.

According to an embodiment of the system, the system can also oralternatively include a third process-to-process heat exchanger unitpositioned to receive bottom stream product from the reactor unit andthe bottom stream product from the naphtha stripper so that the bottomstream product from the reactor unit provides heat energy to the bottomstream product from the naphtha stripper. A conduit is operablyconnected between a bottom stream product outlet port in the reactorunit and a first inlet port in the third heat exchanger unit. Anotherconduit is operably connected between a first outlet port of the secondheat exchanger unit and a reboiling inlet port in the naphtha stripper,with this conduit being in fluid communication through the heatexchanger unit with the conduit connected to the first inlet port.Another conduit is operably connected between a bottom stream productoutlet port in the naphtha stripper and a second inlet port in thesecond heat exchanger unit, and an associated conduit is operablyconnected between a second outlet port of the second heat exchanger unitand a reactor unit product receiving inlet port in the naphtha stripper,with such conduit being in fluid communication through the second heatexchanger unit with the conduit connected to the second inlet port.

Accordingly, in this exemplary configuration, the reactor unit, thenaphtha stripper, and the second heat exchanger unit are operablycoupled so that when operationally employed the bottom stream productfrom the reactor unit flowing through a respective pair of the conduitsand associated portions of the second heat exchanger unit is in thermalcommunication with the bottom stream product from the naphtha stripperflowing through the other pair of conduits and associated portions ofthe second heat exchanger unit to thereby conduct reboiling of thebottom stream product from the naphtha stripper through use of thebottom stream product from the reactor unit. Note, when the secondprocess-to-process heat exchanger is configured to provide sufficientheat exchange capacity to reboil the bottom stream product from thenaphtha stripper without use of a fired heater unit positioned todirectly reboil the bottom stream product from naphtha stripper, thesystem can be and generally is configured to be devoid of a fired heaterunit positioned to directly reboil the bottom stream product fromnaphtha stripper, reducing both utility and capital expenses.

According to an embodiment of the present invention, various sets ofvalves can be included to selectively control fluid flow through thevarious system components including, for example, the second heatexchanger unit. According to an exemplary configuration, the valvesinclude a first set of valves located in the naphtha hydrotreat reactionprocess section for selectively directing the bottom stream product fromthe reactor unit either directly to a third heat exchanger unit orindirectly through the second heat exchanger unit, and can include asecond set of valves located in the naphtha stripping process sectionfor selectively directing the bottom stream product from the naphthastripper either directly to the fired heater or indirectly through thesecond heat exchanger unit. Various other configurations are also withinthe scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and advantages of theinvention, as well as others which will become apparent, may beunderstood in more detail, a more particular description of theinvention briefly summarized above may be had by reference to theembodiments thereof which are illustrated in the appended drawings,which form a part of this specification. It is to be noted, however,that the drawings illustrate only various embodiments of the inventionand are therefore not to be considered limiting of the invention's scopeas it may include other effective embodiments as well.

FIG. 1 is a schematic diagram of a naphtha hydrotreating process/systemto hydrotreat naphtha feedstocks for provision to a refining reformingunit;

FIG. 2 is a schematic diagram of two primary sections of a naphthahydrotreating process/system to hydrotreat naphtha feedstocks forprovision to a refining reforming unit according to an alternativedesign;

FIG. 3 is a schematic diagram of two primary sections of a naphthahydrotreating process/system to hydrotreat naphtha feedstocks forprovision to a refining reforming unit according to an embodiment of thepresent invention;

FIG. 4 is a schematic diagram of two primary sections of a naphthahydrotreating process/system to hydrotreat naphtha feedstocks forprovision to a refining reforming unit according to an embodiment of thepresent invention;

FIG. 5 is a schematic diagram of a naphtha hydrotreating process/systemto hydrotreat naphtha feedstocks for provision to a refining reformingunit according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of the naphtha hydrotreatingprocess/system to hydrotreat naphtha feedstocks for provision to arefining reforming unit of FIG. 5 illustrating the application of valvesaccording to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a naphtha hydrotreating process/systemto hydrotreat naphtha feedstocks for provision to a refining reformingunit according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of a naphtha hydrotreating process/systemto hydrotreat naphtha feedstocks for provision to a refining reformingunit according to an embodiment of the present invention;

FIG. 9 is a schematic flow diagram illustrating steps for hydrotreatingdifferent naphtha feed stocks destined for a refining reforming unit andother applications according to an embodiment of the present invention;

FIG. 10 is a schematic flow diagram illustrating steps for hydrotreatingdifferent naphtha feed stocks destined for a refining reforming unit andother applications according to an embodiment of the present invention;and

FIG. 11 is a schematic flow diagram illustrating steps for hydrotreatingdifferent naphtha feed stocks destined for a refining reforming unit andother applications according to an embodiment of the present invention.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, which illustrate embodiments ofthe invention. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theillustrated embodiments set forth herein. Rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art.Like numbers refer to like elements throughout. Prime notation, if used,indicates similar elements in alternative embodiments.

FIGS. 1-8 provide examples of simulation files including stream data anddetailed simulation results of conventional configurations and thoseaccording to various embodiment of the present invention, to illustratevarious benefits without limiting the various embodiments of theinvention's new energy efficient and environmentally conscious advancedconfigurations for the integrated Naphtha Hydrotreating (NHT) strippingand naphtha splitter processes and special one-heater-only processconfigurations for Hydrotreating stripping and naphtha splittersections.

FIG. 1 illustrates a conventional hydrotreating process/system 30 thatincludes a reaction section 31, a contaminants stripping section 32, anda naphtha splitting section 33. The purpose of such hydrotreatingprocess 30 is to eliminate impurities, mainly sulfur, but also nitrogenand arsenic, which affect the performance and life of the downstreamreforming unit. In the reaction section 31 of this process 30, fullrange naphtha is mixed with hydrocracked naphtha from a hydrocrackingunit (not shown) and with a raffinate stream from an Aromaticsextraction unit (not shown), if any, in a naphtha reactor feed surgedrum 35. The mixture is then pumped to the reaction section 31 where itis mixed with a hydrogen stream. This hydrogen stream is a combinedprocess's recycle stream and a make-up one, as understood by one ofordinary skill in the art.

The mixture is heated up to the reaction temperature viaprocess-to-process heat exchanger(s) 37 and a fired heater 39. Theexemplary reaction section 31 is using a vapor phase reactor 41 wherethe hydrogenation, desulphurization, denitrogenation reactions aretaking place on a hydrotreatment catalyst. The reactor effluent (bottomproduct from the reactor 41) is cooled down using a combination of theprocess-to-process heat exchanger 37 and an air/water cooler(s) 43. Thecooled effluent is then pumped to a two- or three-phase separator 45(e.g., knockout drum) to separate the gases from the liquid phase. Mostof the separated gas is used as a recycle gas and is sent back to thereactor feed via a compressor 47. The rest, e.g., small part (notshown), of these gases are purged to a fuel gas system/network 49 tocontrol the reaction section pressure.

The hydrocarbon liquid phase from the reaction section separation drum45 is used as a feed to a hydrotreating naphtha stripper column/unit(naphtha stripper) 51 of the stripping section 32. The stripper 51receives the feed through fluid pathway 53. The feed flowing throughfluid pathway 53 is first preheated against the stripper bottom stream(stabilized naphtha) flowing through fluid pathway 55 in aprocess-to-process heat exchanger unit 57. The stripper bottom productflowing through fluid pathway 55 is then sent to a naphtha splittercolumn/unit (naphtha splitter) 61 of the naphtha splitter section 33after being preheated by a process-to-process heat exchanger unit 63.Stripper reboiling is conducted by a fired heater 59 and circulatingpump (not shown) which receives stripper bottom product either directlyfrom a lower portion of the stripper or through a tap in fluid pathway55.

Note, one of ordinary skill in the art would understand that referenceto a fluid pathway includes reference to the various types of fluidcarrying pathways and/or pipelines or other fluid carrying conduits,continuous or in sections interlaced with various components includingvalves, bypasses, taps, etc. Also, when referring to a fluid pathwayextending to and beyond a heat exchanger unit, reference may be made tothe fluid pathway being a single conduit/pipeline or two separateconduits/pipelines to form a single functional pathway with the firstconduit/pipeline connected to an inlet in the heat exchanger and thesecond conduit/pipeline connected to an outlet of the heat exchanger.

The stripper overhead product is partially condensed, normally using anair cooler 65 and water cooler 66, and sent to a reflux drum 67. Liquidphase from the drum 67 is used as a reflux to the stripper column 51.The vapor phase from the reflux drum 67 is sent to the fuel gassystem/network 49.

As noted above, the naphtha splitter column 61 of the naphtha splittersection 33 receives the stabilized naphtha (from stripper bottomproduct) flow through fluid pathway 55 as its feed, which is receivedafter being preheated by process-to-process heat exchanger unit 57 andthen by process-to-process heat exchanger unit 63. Reboiling of thenaphtha splitter column 61 is normally conducted using a fired heater ormedium pressure (MP) steam reboiler 69, which receives splitter bottomproduct via a fluid pathway 71 connected either directly from a lowerportion of the splitter or through a tap in fluid pathway 72. Fluidpathway 72 provides heavy naphtha from the splitter bottom which ispumped and sent to a downstream reforming unit and/or storage tanks 73after being cooled against the naphtha splitter column feed in aprocess-process heat exchanger 63, air cooler 75 and water cooler 76.

The naphtha splitter overhead is fully condensed in an air cooler 82 andsent to reflux drum 83 where part is used as a reflux to the naphthasplitter column and the rest is normally sent to an Isomerization unit(not shown) or associated storage unit 85.

FIG. 2 illustrates in alternative configuration to the conventionalHydrotreating process 30 shown in FIG. 1 whereby heat exchanger unit 63is positioned in line with the feed to the stripper column 51 flowingthrough fluid pathway 53 rather than the stripper bottom product flowingthrough fluid pathway 55.

As noted previously, most of the old and recently built NHT plants useeither Axens or UOP processes, with the two processes being almost thesame. These two processes, shown in FIGS. 1 and 2, respectively, do notexhibit direct integration between the two stripping and naphthasplitting sections 32, 33. The feeds of the respective sections for bothprocesses are preheated by one or more of the bottom products and theextra waste heat in the heavy naphtha stream is sent to the air andwater coolers. The configuration illustrated in FIG. 1 is a little moreefficient from an energy point of view than the configurationillustrated in FIG. 2, since it sends the heavy naphtha stream to theair and water coolers 75, 76 at a little lower temperature than theconfiguration illustrated in FIG. 2. Accordingly, the configurationillustrated in FIG. 1 provides a possible optimal base case for the sakeof a benefits comparison between the conventional hydrotreatingprocesses and those featured hydrotreating processes according to one ormore embodiments of the present invention.

FIG. 3 illustrates an example of an embodiment of the present inventionwhereby the hydrotreating stripping section 32 and the naphtha splittersections 33 are modified to provide direct integration between the twosections to reduce both the heating and cooling utilities, as well asthe associated energy-based emissions. The exemplary configuration shownin the figure, for example, reduces both the hot load on the naphthasplitter section fired heater by 37% (e.g., 64 MMBTU/h less in theexemplary configuration of FIG. 3 from that of the configuration shownin FIG. 1) resulting in a reduction of the energy-based green house gasemissions by almost the same percentage for the section of the process,and a reduction in the cooling utilities duty requirement for thesection of the process by 64% (e.g., 64 MMBTU/h less in the exemplaryconfiguration of FIG. 3 from that of the configuration shown in FIG. 1).According to the illustrated example, such savings are obtained by usingthe stripper bottom product stream as one of two pivotal streams fordirect heat integration between the hydrotreating stripper and naphthasplitter processes sections 32, 33. The second pivotal stream for suchdirect integration between the two process sections 32, 33 is thenaphtha splitter bottom product (heavy naphtha feed stream) destined forthe reforming unit.

According to the illustrated configuration, the hydrotreating strippingsection 32 receives the hydrocarbon liquid phase feed from the reactionsection separation drum 45 after being preheated against the naphthasplitter heavy naphtha product stream and the naphtha hydrotreatingstripper bottom stream, respectively, via process-to-process heatexchangers 63′ and 57. As in the prior described configurations, thestripper bottom product is then sent to naphtha splitter column 61, andthe stripper overhead product is partially condensed, using an aircooler 65, and is sent to the reflux drum 67. Liquid phase from suchdrum 67 is used as a reflux to the stripper column 51, and the vaporphase from the reflux drum 67 is sent to the fuel gas system/network 49.

According to the new naphtha splitter section configuration,intra-integrated with the hydrotreating stripping section 32, theprocess is conducted via the continual receiving of the stabilizednaphtha coming from stripper bottom product in the naphtha splittercolumn 61, but the reboiling of the naphtha splitter column 61 is nowconducted using the stripper bottom product in combination with thefired heater 69. Specifically, an additional process-to-process heatexchanger 81 is positioned in the pathway of the reboiling stream forthe naphtha splitter column 61, i.e., fluid pathway 71, and in thepathway of the stripper bottom stream (stabilized naphtha) flowingthrough fluid pathway 55. Beneficially, in the exemplary configuration,this utilization of the hydrotreating stripping section bottom productto assist in reboiling of the heavy naphtha bottom product results inthe hot load savings of 37% in the fired heaters for the naphthasplitter section 33.

As per the conventional process, the naphtha splitter overhead is fullycondensed in an air cooler 82 and is sent to the reflux drum 83 wherepart of the condensed liquid is used as a reflux to the naphtha splittercolumn 61 and the rest is sent to an Isomerization unit and/or stored ina storage unit 85 for later use.

As noted above, heavy naphtha feed from the splitter column bottom ispumped and sent to a reforming unit downstream and/or storage tanks 73.According to the enhanced naphtha splitter section configuration, heatexchanger 63 illustrated in FIGS. 1-2, is provided additional surfacearea or is otherwise modified/replaced in favor of heat exchanger unit63′ (FIG. 3) to provide aggressive cooling of the naphtha splitterbottom product flowing through fluid pathway 72 against thehydrotreating stripper feed stream flowing through fluid pathway 55.

This aggressive cooling of the heavy naphtha bottom stream product fromthe naphtha splitter column 61 performed before being sent to an aircooler 75 and/or water cooler 76 and before any other usage, results inthe exemplary 64% saving in the naphtha splitter section air/watercooling utility. In fact, the efficiency of heat exchanger unit 63′ cannegate a need for a water cooler(s) and reduce the number and amount ofrequired air fin coolers 75. For example, the improved configuration ofFIG. 3 made upon the system of the FIG. 1 can reduce total heatingutility for the combined stripper and splitter sections 32, 33, from 300MMBTU/h to 236 MMBTU/h and total cooling utility from 100 MMBTU/h to 36MMBTU/h. Further, such reduction in cooling utility requirements cannegate a need for capital spending of water coolers, and can reducecapital costs for air fin fan coolers.

FIG. 4 illustrates a special case according to an embodiment of thepresent invention, where one fired heater only (e.g., fired heater 59)is desired. In such case, fired heater 69 can be removed or bypassed andthe stripper reboiling can be conducted via heat exchange of portions ofthe naphtha splitter column reboiling stream with the reboiling streamdestined for the stripper fired heater 69.

In such configuration, an additional process-to-process heat exchanger91 configured to receive the naphtha splitter column reboiling streamflowing through the reboiling stream fluid pathway 93 and the strippercolumn reboiling stream flowing through reboiling stream fluid pathway95 enroute to the stripper fired heater 59 provides reboiling of thesplitter column reboiling stream with the stripper column reboilingstream. Fluid pathway 93 can be connected either directly from a lowerportion of the splitter column 61 or through a tap in fluid pathway 71.Similarly, fluid pathway 95 can be connected either directly from alower portion of the stripper column 51 or through a tap in fluidpathway 55. According to the exemplary configuration, a bypass conduit97 and valve 99 can be provided to allow bypass of the heat exchanger 91and/or to adjust the amount of flow of stripper bottom stream productthrough heat exchanger 91 to provide sufficient reboiling of the naphthasplitter column bottom stream product.

Beneficially, this special configuration, while it increases the thermalload on the stripper bottoms fired heater 59, enables the deletion ofthe naphtha splitter fired heater/steam reboiler(s) 69 by using theadditional heat exchanger 91 in conjunction with an increase in the sizeof the stripper section fired heater 59, if needed to meet capacity.

FIGS. 5 and 6 provide examples of direct integration of thehydrotreating stripper section 32 with the reaction section 31, which isalso integrated with the naphtha splitter section 33 as described withrespect to FIG. 3. According to the illustrated embodiments, at leastportions of the stripper reboiling stream (diverted through fluidpathway 101) is heated in a process-to-process heat exchanger 103 thatexchanges heat with reactor section effluent diverted through fluidpathway 105. This configuration beneficially reduces the load on thestripper fired heater by approximately 101 MMBTU/h (from 127.7 MMBTU/hdown to 27 MMBTU/h), and can reduce overall heating utility requirementsfor the three sections 31, 32, 33, from 374 MMBTU/h to 267 MMBTU/h andthe overall cooling utility requirements from 172 MMBTU/h to 65 MMBTU/h.

According to the illustrated configuration of FIG. 6, valve 111positioned within fluid pathway 95 can be used in conjunction with valve113 positioned within fluid pathway 101 to control an amount of fluidflow diverted from fluid pathway 95, up to a complete diversion followedby a complete reintroduction. Similarly, valve 115 positioned withinfluid pathway 117 can be used in conjunction with valve 119 within thefluid pathway 105 to control an amount of reactor effluent diverted fromfluid pathway 117, up to a complete diversion followed by a completereintroduction. The fluid pathway 101 can be connected either directlyfrom a lower portion of the stripper column 51 (as shown) or via a tapin fluid pathway 95, and is connected at the end of the pathway to areturn tap in fluid pathway 95. Similarly, fluid pathway 105 can beconnected either directly from a lower portion of the reactor 41 athrough a tap in fluid pathway 117 (as shown), and is connected at theend of the pathway to a return tap in fluid pathway 117. Additionally,valve 120 can control the amount of fluid entering heat exchanger 63′ tocontrol the amount of cooling of heavy naphtha feedstock performeden-route to the continuous catalyst circulation reactor (CCR) units.

FIG. 7 provides a similar exemplary configuration to that shown in FIG.5, but utilizing a higher surface area process-to-process heat exchangerunit 103′ and/or higher flow rate capacities, further reducing themeeting utility requirements of the stripper fired heater 59 down to 14MMBTU/h, and reducing overall heating utility and cooling utilityrequirements each by approximately 15 MMBTU/h.

FIG. 8 provides another similar example utilizing an even higher surfacearea process-to-process heat exchanger unit 103″ and/or flow ratecapacity. In this particular configuration, the capacity of the heatexchanger unit 103″ is sufficient to negate a need for the stripperfired heater 59 which can be either bypassed or, along with fluidpathway 95, can be removed/recycled. That is, heat exchanger unit 103″provides a heat exchange capacity of greater than the 127.7 MMBTU/h, andthus, reboiling can be accomplished solely through direct integrationwith the reactor section 31. Accordingly, in the illustratedconfiguration, fluid pathway 101′ extends between a lower portion of thestripper column 51 at its inlet and the fired heater port in the side ofstripper column 51 at its end to provide a complete reboiling circuitdevoid of a fired heater. Additionally, as described with respect toFIG. 6, valves 115, 119 can be operated together to control the amountof reactor effluent delivered to heat exchanger unit 103″ to therebycontrol reboiling temperatures.

FIG. 9 provides a flow diagram illustrating steps for providinghydrotreated naphtha feedstocks to a refining reforming unit accordingto an example embodiment of the present invention. Referring also toFIG. 3, the method includes the step of directly integrating a naphthastripping process section 32 including a naphtha stripping column/unit(e.g., naphtha stripper 51) with a naphtha splitting process section 33including a naphtha stripper column/unit (e.g., naphtha stripper 61)(block 200). The step of directly integrating includes providing areboiling process-to-process heat exchanger unit 81 receiving a bottomstream product of heavy naphtha from a naphtha splitter 61 and a bottomstream product from a naphtha stripper 51 to transfer heat from thebottom stream product from the naphtha stripper 51 to bottom streamproduct from the naphtha splitter 61 (block 201), providing a firedheater unit 69 operably connected in line with and downstream of thereboiling process-to-process heat exchanger 81 to provide additionalheat to the bottom stream product from the naphtha splitter 61 needed toreboil bottom stream product from naphtha splitter 61 (block 203), andconducting reboiling of heavy naphtha bottom stream product from thenaphtha splitter 61 utilizing the naphtha stripper bottom stream productfrom the naphtha stripper 51 in conjunction with the fired heater unit69 (block 205). The step of directly integrating a naphtha strippingprocess section 32 with a naphtha splitting process section 33 can alsoinclude providing a high-capacity second process-to-process heatexchanger unit 63′ receiving the bottom stream product of heavy naphthafrom the naphtha splitter 61 and reactor product from a reactor unit 41of a reaction process section 31 to aggressively cool the heavy naphthabottom stream product from the naphtha splitter 61 providing reformingfeed to a refining reforming unit, to less than approximately 200° F.,and more preferably approximately 173° F. (block 207). Beneficially,such configuration can facilitate further downstream cooling of theheavy naphtha bottom stream product using an air cooler 75 positioned toreceive the heavy naphtha bottom stream product from the naphthasplitter 61, to an extent that the combination of secondprocess-to-process heat exchanger unit 63′ and air cooler 75 issufficient to negate a need for a non air-cooled chilling unit.

FIG. 10 provides a flow diagram illustrating steps for providinghydrotreated naphtha feedstocks to a refining reforming unit accordingto another example embodiment of the present invention. Referring alsoto FIG. 4, the method includes the step of directly integrating anaphtha stripping process section 32 with a naphtha splitting processsection 33 (block 220). The step of directly integrating sections 32, 33includes providing a first reboiling process-to-process heat exchangerunit 81 receiving a bottom stream product of heavy naphtha from anaphtha splitter 61 and a bottom stream product from a naphtha stripper51 to transfer heat from the bottom stream product from the naphthastripper 51 to the bottom stream product from the naphtha splitter(block 221), providing a second reboiling heat exchanger unit 91operably receiving additional bottom stream product from the naphthastripper 51 and additional bottom stream product from the naphthasplitter 61 so that the additional bottom stream product from thenaphtha stripper 51 provides heat energy to the additional bottom streamproduct from the naphtha splitter 61 to reboil the additional bottomstream product from the naphtha splitter init 61 (block 223), andproviding a fired heater unit 55 operably connected in line with anddownstream of the second process-to-process heat exchanger 91 to reboilbottom stream product from naphtha stripper 51 (block 225) to replenishheat transferred to the bottom stream product from the naphtha stripper51 to bottom stream product from the naphtha splitter 61 and to applyadditional heat thereto.

The direct integration between sections 32, 33 can also includeconducting the reboiling of the heavy naphtha bottom stream product fromthe naphtha splitter 61 utilizing both the first process-to-process heatexchanger unit 81 (receiving heat from the naphtha stripper bottomstream product providing feed to the naphtha splitter 61) and the secondreboiling process-to-process heat exchanger unit 91 (receiving heat fromthe naphtha stripper bottom stream product enroute to the fired heaterunit 55) (block 227). Beneficially, according to this exemplaryconfiguration, the first and the second reboiling process-to-processheat exchanger units 81, 91, are collectively configured to providesufficient heat exchange capacity to reboil the bottom stream productfrom the naphtha splitter 61 without use of a fired heater unit (e.g.heater unit 69, FIG. 1) positioned to directly reboil the bottom streamproduct from naphtha splitter 61.

The step of directly integrating sections 32, 33 can further includeproviding a high-capacity third process-to-process heat exchanger unit63′ receiving the bottom stream product of heavy naphtha from thenaphtha splitter 61 and reactor product from a reactor unit 41 of thereaction process section 31 to aggressively cool the heavy naphthabottom stream product from the naphtha splitter 61 providing a reformingfeed to a refining reforming unit, to a value less than 200° F., andmore preferably approximately 173° F. (block 229). Beneficially, suchconfiguration can facilitate further downstream cooling of the heavynaphtha bottom stream product using an air cooler 75 positioned toreceive the heavy naphtha bottom stream product from the naphthasplitter 61, to an extent that the combination of the thirdprocess-to-process heat exchanger 63′ and air cooler 75 is sufficient tonegate a need for a non air-cooled chilling unit to cool the feed.

FIG. 11 provides a flow diagram illustrating steps for providinghydrotreated naphtha feedstocks to a refining reforming unit accordingto another example embodiment of the present invention. Referring alsoto FIGS. 5 & 6, the method includes the step of directly integrating anaphtha stripping process section 32 with a naphtha splitting processsection 33 (block 230), and directly integrating a naphtha hydrotreatreaction process section 31 with the naphtha stripping process section32 (block 240). The step of directly integrating the naphtha strippingprocess section 32 with the naphtha splitting process section 33includes, for example: providing a first (reboiling) process-to-processheat exchanger unit 81 receiving a bottom stream product of heavynaphtha from a naphtha splitter 61 and a bottom stream product from anaphtha stripper 51 to transfer heat from the bottom stream product fromthe naphtha stripper 51 to the bottom stream product from the naphthasplitter 61 (block 231), providing a fired heater unit 69 operablyconnected in line with and downstream of the first process-to-processheat exchanger 81 to provide additional heat to the bottom streamproduct from the naphtha splitter 61 needed to reboil bottom streamproduct from naphtha splitter 61 (block 233), and conducting reboilingof heavy naphtha bottom stream product from the naphtha splitter 61utilizing the naphtha stripper bottom stream product from the naphthastripper 51 in conjunction with the fired heater unit 69 connected inline with and downstream of the first reboiling process-to-process heatexchanger 81 (block 235).

The step of directly integrating sections 32, 33 can also includeproviding a high-capacity second (heat transfer) process-to-process heatexchanger unit 63′ receiving the bottom stream product of heavy naphthafrom the naphtha splitter 61 and reactor product from the reactor unit41 of the reaction process section 31 to aggressively cool the heavynaphtha bottom stream product from the naphtha splitter 61 (providingreforming feed to a refining reforming unit) to less than 200° F., andmore preferably approximately 173° F. (block 237).

The step of directly integrating a naphtha hydrotreat reaction processsection 32 with the naphtha stripping process section 31 includes, forexample: providing a third (reboiling) process-to-process heat exchangerunit 103, 103′, 103″ receiving bottom stream product from the reactorunit 41 and the bottom stream product from the naphtha stripper 51 sothat the bottom stream product from the reactor unit 41 provides heatenergy to the bottom stream product from the naphtha stripper (block241), and conducting reboiling of naphtha stripper bottom stream productreceived from the naphtha stripper 51 by the third (reboiling)process-to-process heat exchanger unit 103, 103′, 103″ through use ofthe reactor unit bottom stream product received from the reactor unit 41by the third (reboiling) process-to-process heat exchanger unit 103,103′, 103″ (block 243).

Referring also to FIGS. 7 & 8, the step of providing the third(reboiling) process-to-process heat exchanger unit 103, 103′, 103″ caninclude increasing the surface area of the heat exchanger unit 103,103′, 103″ and/or increasing the flow rate of the bottom stream productfrom the reactor unit 41 and/or the flow rate of the bottom streamproduct from the naphtha stripper 51 as necessary to reduce the amountof heating utility required for reboiling the stripper bottom streamproduct, up to an extent of providing sufficient heat exchange capacityto reboil the bottom stream product from the naphtha stripper 51 withoutuse of the fired heater unit 59 positioned to directly reboil the bottomstream product from naphtha stripper 51.

FIGS. 7 and 8 beneficially illustrate that various configurations can beobtained/derived from the base configuration shown in FIGS. 5 and 6 withthe various benefits described previously, but with differentlevels/values for energy consumption savings, greenhouse gas emissionreductions, and waste heat recovery according to an easily managedconfiguration retrofittable for future energy and greenhouse gasreductions. Additionally, such base configuration provides for betterflexibility (lower β ratio) in the reaction section heater according tothe changing needs/desires/objectives/economics of the process owners,which generally differ from one location to another.

In the drawings and specification, there have been disclosed a typicalpreferred embodiment of the invention, and although specific terms areemployed, the terms are used in a descriptive sense only and not forpurposes of limitation. The invention has been described in considerabledetail with specific reference to these illustrated embodiments. It willbe apparent, however, that various modifications and changes can be madewithin the spirit and scope of the invention as described in theforegoing specification.

1-13. (canceled)
 14. A system to hydrotreat naphtha feedstocks forprovision to a refining reforming unit, the system comprising: a naphthasplitting process section including a naphtha splitter providing heavynaphtha bottom stream product to a refining reforming unit; a naphthastripping process section including a naphtha stripper providing bottomstream product to the naphtha splitter; a naphtha hydrotreat reactionprocess section including a reactor unit providing bottom stream productto the naphtha stripper; a process-to-process heat exchanger unitpositioned to receive bottom stream product from the naphtha stripperand bottom stream product of heavy naphtha from the naphtha splitter sothat the bottom stream product from the naphtha stripper provides heatenergy to the bottom stream product from the naphtha splitter; a firstconduit operably connected between a bottom stream product outlet portof the naphtha stripper and a first inlet port in the heat exchangerunit; a second conduit operably connected between a first outlet port ofthe heat exchanger unit and a naphtha stripper bottom stream productreceiving inlet port in the naphtha splitter, the second conduit influid communication with the first conduit through the heat exchangerunit; a third conduit operably connected between a bottom stream productoutlet port of the naphtha splitter and a second inlet port in the heatexchanger unit; and a fourth conduit operably connected between a secondoutlet port of the heat exchanger unit and a reboiling inlet port in thenaphtha splitter, the fourth conduit in fluid communication with thethird conduit through the heat exchanger unit, the naphtha splitter, thenaphtha stripper, and the heat exchanger unit operably coupled so thatwhen operationally employed the bottom stream product from the naphthastripper flowing through the first and the second conduits andassociated portions of the heat exchanger unit is in thermalcommunication with the bottom stream product from the naphtha splitterflowing through the third and the fourth conduits and associatedportions of the heat exchanger unit to thereby conduct reboiling of thenaphtha bottom stream product from the naphtha splitter through use ofthe bottom stream product from the naphtha stripper.
 15. A system asdefined in claim 14, wherein the process-to-process heat exchanger unitis a first heat exchanger unit, the system further comprising: ahigh-heat-transfer capacity second process-to-process heat exchangerunit positioned to receive condensed portions of bottom stream productfrom the reactor unit and the bottom stream product from the naphthasplitter so that the condensed portions of the bottom stream productfrom the reactor unit extracts substantial heat energy from the bottomstream product from the naphtha splitter; a fifth conduit operablyconnected between a bottom stream product outlet port in the reactorunit and a first inlet port in the second heat exchanger unit; a sixthconduit operably connected between a first outlet port of the secondheat exchanger unit and a naphtha feed inlet port in the naphthastripper, the sixth conduit in fluid communication with the fifthconduit through the second heat exchanger unit; a seventh conduitoperably connected between a bottom stream product outlet port in thenaphtha splitter and a second inlet port in the second heat exchangerunit; and an eighth conduit operably connected between a second outletport of the second heat exchanger unit and hydrotreated product feedinlet port in a catalytic reformer unit, the eighth conduit in fluidcommunication with the seventh conduit through the second heat exchangerunit, the reactor unit, the naphtha stripper, and the second heatexchanger unit operably coupled so that when operationally employed thebottom stream product from the reactor unit flowing through the fifthand the sixth conduits and associated portions of the second heatexchanger unit is in thermal communication with the bottom streamproduct from the naphtha splitter flowing through the seventh and theeighth conduits and associated portions of the second heat exchangerunit to thereby cool the bottom stream product from the naphtha splitterthrough use of the bottom stream product from the reactor unitsufficiently to negate a need for a non-air cooled chilling unit to beemployed between the second outlet port of the second heat exchanger andthe hydrotreated product feed inlet port in a catalytic reformer unit.16. A system as defined in claim 15, further comprising: an air cooleroperably coupled to the second heat exchanger unit and the catalyticreformer unit to receive the heavy naphtha bottom stream product fromthe naphtha splitter and to provide cooled bottom stream product fromthe naphtha splitter to the catalytic reformer unit; and wherein atemperature of the heavy naphtha bottom stream product provided to thecatalytic reformer unit is less than 200° F.
 17. A system as defined inclaim 14, wherein the process-to-process heat exchanger unit is a firstreboiling heat exchanger unit, the system further comprising: a firedheater unit operably positioned to reboil bottom stream product from thenaphtha stripper, the fired heater including a naphtha stripper bottomstream product receiving inlet port and a heated naphtha stripper bottomstream product outlet port in fluid communication with the naphthastripper; a second reboiling heat exchanger unit positioned to receiveadditional bottom stream product from the naphtha stripper andadditional bottom stream product of heavy naphtha from the naphthasplitter so that the additional bottom stream product from the naphthastripper provides heat energy to additional bottom stream product fromthe naphtha splitter to reboil the additional bottom stream product fromthe naphtha splitter; a fifth conduit operably connected between abottom stream product outlet port of the naphtha stripper and a firstinlet port in the second reboiling heat exchanger unit; a sixth conduitoperably connected between a first outlet port of the second reboilingheat exchanger unit and the naphtha stripper bottom stream productreceiving inlet port in the fired heater unit, the fifth conduit influid communication with the sixth conduit through the second reboilingheat exchanger unit; a seventh conduit operably connected between abottom stream product outlet port of the naphtha splitter and a secondinlet port in the second reboiling heat exchanger unit; and an eighthconduit operably connected between a second outlet port of the secondreboiling heat exchanger unit and the reboiling inlet port in thenaphtha splitter, the fourth conduit in fluid communication with thethird conduit through the second reboiling heat exchanger unit, thenaphtha splitter, the naphtha stripper, the fired heater unit, and thesecond reboiling heat exchanger operably coupled so that whenoperationally employed the bottom stream product from the naphthastripper flowing through the fifth and the sixth conduits and associatedportions of the second reboiling heat exchanger unit is in thermalcommunication with the bottom stream product from the naphtha splitterflowing through the seventh and the eighth conduits and associatedportions of the second reboiling heat exchanger unit to thereby conductreboiling of the additional naphtha bottom stream product from thenaphtha splitter through use of the additional bottom stream productfrom the naphtha stripper prior to return of the additional naphthastripper bottom stream product to the naphtha stripper through the firedheater, and the first and the second reboiling heat exchangersconfigured to provide sufficient total capacity to reboil the naphthabottom stream product from the naphtha splitter without use of a firedheater unit positioned to directly reboil bottom stream product from thenaphtha splitter, and wherein the system is devoid of a fired heaterunit positioned to directly reboil bottom stream product from thenaphtha splitter.
 18. A system as defined in claim 14, wherein theprocess-to-process heat exchanger unit is a first heat exchanger unit,the system further comprising: a second process-to-process heatexchanger unit positioned to receive bottom stream product from thereactor unit and the bottom stream product from the naphtha stripper sothat the bottom stream product from the reactor unit provides heatenergy to the bottom stream product from the naphtha stripper; a fifthconduit operably connected between a bottom stream product outlet portin the reactor unit and a first inlet port in the second heat exchangerunit; a sixth conduit operably connected between a first outlet port ofthe second heat exchanger unit and a reboiling inlet port in the naphthastripper, the sixth conduit in fluid communication with the fifthconduit through the heat exchanger unit; a seventh conduit operablyconnected between a bottom stream product outlet port in the naphthastripper and a second inlet port in the second heat exchanger unit; andan eighth conduit operably connected between a second outlet port of thesecond heat exchanger unit and a reactor unit product receiving inletport in the naphtha stripper, the eighth conduit in fluid communicationwith the seventh conduit through the second heat exchanger unit, thereactor unit, the naphtha stripper, and the second heat exchanger unitoperably coupled so that when operationally employed the bottom streamproduct from the reactor unit flowing through the fifth and the sixthconduits and associated portions of the second heat exchanger unit is inthermal communication with the bottom stream product from the naphthastripper flowing through the seventh and the eighth conduits andassociated portions of the second heat exchanger unit to thereby conductreboiling of the bottom stream product from the naphtha stripper throughuse of the bottom stream product from the reactor unit.
 19. A system asdefined in claim 18, wherein the second process-to-process heatexchanger is configured to provide sufficient heat exchange capacity toreboil the bottom stream product from the naphtha stripper without useof a fired heater unit positioned to directly reboil the bottom streamproduct from naphtha stripper; and wherein the system is devoid of afired heater unit positioned to directly reboil the bottom streamproduct from naphtha stripper.
 20. A system as defined in claim 18,further comprising: a fired heater unit operably positioned to reboilbottom stream product from the naphtha stripper; a thirdprocess-to-process heat exchanger unit positioned to receive naphthadistillate distilled from a crude oil distiller and the bottom streamproduct from the reactor unit so that the naphtha distillate extractsheat energy from the bottom stream product from the reactor unit; and aplurality of valves positioned to selectively control fluid flow throughthe second heat exchanger unit, the plurality of valves including afirst set of valves located in the naphtha hydrotreat reaction processsection for selectively directing bottom stream product from the reactorunit either directly to the third heat exchanger unit or indirectlythrough the second heat exchanger unit, and a second set of valveslocated in the naphtha stripping process section for selectivelydirecting the bottom stream product from the naphtha stripper eitherdirectly to the fired heater or indirectly through the second heatexchanger unit.
 21. A system to hydrotreat naphtha feedstocks forprovision to a refining reforming unit, the system comprising: a naphthastripping process section directly integrated with a naphtha splittingprocess section to enhance energy efficiency of a naphtha hydrotreatingprocess; a process-to-process heat exchanger unit positioned to receivebottom stream product of heavy naphtha from a naphtha splitter andbottom stream product from a naphtha stripper, such that the bottomstream product from the naphtha stripper provides heat energy to thebottom stream product from the naphtha splitter; and the naphthasplitter, the naphtha stripper, and the heat exchanger unit operablycoupled to conduct reboiling of heavy naphtha bottom stream product fromthe naphtha splitter, the reboiling conducted utilizing naphtha stripperbottom stream product from the naphtha stripper.
 22. A system as definedin claim 21, comprising a fired heater unit connected in line with anddownstream of the process-to-process heat exchanger, wherein thereboiling of naphtha bottom stream product from the naphtha splitterfurther utilizes the fired heater unit.
 23. A system as defined in claim21, wherein the process-to-process heat exchanger unit is a firstreboiling process-to-process heat exchanger unit configured to transferheat from bottom stream product from the naphtha stripper to bottomstream product from the naphtha splitter, the system further comprising:a fired heater unit positioned to reboil bottom stream product fromnaphtha stripper; a second reboiling heat exchanger unit positioned toreceive additional bottom stream product from the naphtha stripper andadditional bottom stream product from the naphtha splitter so that theadditional bottom stream product from the naphtha stripper provides heatenergy to the additional bottom stream product from the naphtha splitterto reboil the additional bottom stream product from the naphthasplitter; and wherein the reboiling of naphtha bottom stream productfrom the naphtha splitter further utilizes the first and the secondreboiling process-to-process heat exchanger units.
 24. A system asdefined in claim 23, wherein the first and the second reboilingprocess-to-process heat exchanger units are collectively configured toprovide sufficient heat exchange capacity to reboil the bottom streamproduct from the naphtha splitter without use of a fired heater unitpositioned to directly reboil the bottom stream product from naphthasplitter, the naphtha splitting process section being devoid of a firedheater unit.
 25. A system as defined in claim 21, wherein theprocess-to-process heat exchanger unit is a first reboilingprocess-to-process heat exchanger unit configured to transfer heat frombottom stream product from the naphtha stripper to bottom stream productfrom the naphtha splitter, the system comprising: a naphtha hydrotreatreaction process section directly integrated with the naphtha strippingprocess section to further enhance energy efficiency of the naphthahydrotreating process: a second reboiling process-to-process heatexchanger unit positioned to receive bottom stream product from thereactor unit and the bottom stream product from the naphtha stripper sothat the bottom stream product from the reactor unit provides heatenergy to the bottom stream product from the naphtha stripper; and thereactor unit, the naphtha stripper, and the second reboilingprocess-to-process heat exchanger unit operably coupled to conductreboiling of naphtha stripper bottom stream product received from thenaphtha stripper utilizing the reactor unit bottom stream productreceived from the reactor unit by the second reboilingprocess-to-process heat exchanger unit
 26. A system as defined in claim25, wherein the second reboiling process-to-process heat exchanger unitis configured to provide sufficient heat exchange capacity to reboil thebottom stream product from the naphtha stripper without use of a firedheater unit positioned to directly reboil the bottom stream product fromnaphtha stripper, the naphtha stripping process section being devoid ofa fired heater unit.
 27. A system as defined in claim 25, comprising: afirst set of valves located in the naphtha hydrotreat reaction processsection positioned for selectively directing the bottom stream productfrom the reactor unit either directly to a third heat exchanger unitpositioned to receive naphtha distillate distilled from a crude oildistiller and the bottom stream product from the reactor unit orindirectly through the second reboiling process-to-process heatexchanger unit, and a second set of valves located in the naphthastripping process section positioned for selectively directing thebottom stream product from the naphtha stripper either directly to thefired heater or indirectly through the second reboilingprocess-to-process heat exchanger unit, the first and the second sets ofvalves being adjustable so that both the bottom stream product from thenaphtha stripper and the bottom stream product from the reactor unitflow through the second reboiling process-to-process heat exchanger unitwhen reboiling the bottom stream product from the naphtha stripper usingthe bottom stream product from the reactor unit is desired, and beingadjustable so that neither of the streams flow through the secondreboiling process-to-process heat exchanger unit when reboiling of thebottom stream product from the naphtha stripper using the bottom streamproduct from the reactor unit is not desired.
 28. A system to hydrotreatnaphtha feedstocks for provision to a refining reforming unit, thesystem comprising: a naphtha stripping process section including anaphtha stripper column directly integrated with a naphtha splittingprocess section including a naphtha splitter column, to enhance energyefficiency of a naphtha hydrotreating process: a first reboilingprocess-to-process heat exchanger unit positioned to receive a bottomstream product of heavy naphtha from the naphtha splitter column and abottom stream product from the naphtha stripper column to transfer heatfrom the bottom stream product from the naphtha stripper column to thebottom stream product from the naphtha splitter column to reboil thebottom stream product from the naphtha splitter column; a secondreboiling heat exchanger unit positioned to receive additional bottomstream product from the naphtha stripper column and additional bottomstream product from the naphtha splitter column such that the additionalbottom stream product from the naphtha stripper column provides heatenergy to the additional bottom stream product from the naphtha splittercolumn to reboil the additional bottom stream product from the naphthasplitter column; a fired heater unit connected in line with anddownstream of the second process-to-process heat exchanger unit toreboil bottom stream product from naphtha stripper column to replenishheat transferred from the bottom stream product from the naphthastripper column to the additional bottom stream product from the naphthasplitter column and to apply additional heat thereto; and wherein thefirst reboiling process-to-process heat exchanger unit and the secondreboiling process-to-process heat exchanger unit are operably coupled toconduct reboiling of the heavy naphtha bottom stream product from thenaphtha splitter column, the first and the second reboilingprocess-to-process heat exchanger units collectively configured toprovide sufficient heat exchange capacity to reboil the bottom streamproduct from the naphtha splitter column without use of a fired heaterunit positioned to directly reboil the bottom stream product fromnaphtha splitter column.
 29. A system as defined in claim 28,comprising: a high-capacity third process-to-process heat exchanger unitpositioned to receive the bottom stream product of heavy naphtha fromthe naphtha splitter column and reactor product from a reactor unit of areaction process section to cool the heavy naphtha bottom stream productfrom the naphtha splitter column to approximately 173° F. to therebyfacilitate further downstream cooling of the heavy naphtha bottom streamproduct using an air cooler positioned to receive the heavy naphthabottom stream product from the naphtha splitter column, to an extentthat the combination of third process-to-process heat exchanger unit andair cooler is sufficient to negate a need for a non-air-cooled chillingunit.
 30. A system to hydrotreat naphtha feedstocks for provision to arefining reforming unit, the system comprising: a naphtha splittingprocess section including a naphtha splitter providing heavy naphthabottom stream product to a refining reforming unit; a naphtha strippingprocess section including a naphtha stripper providing bottom streamproduct to the naphtha splitter; and a heat exchanger unit positioned toreceive bottom stream product from the naphtha stripper and bottomstream product of heavy naphtha from the naphtha splitter so that thebottom stream product from the naphtha stripper provides heat energy tothe bottom stream product from the naphtha splitter, the naphthasplitter, the naphtha stripper, and the heat exchanger unit operablycoupled to thereby conduct reboiling of the naphtha bottom streamproduct from the naphtha splitter through use of the bottom streamproduct from the naphtha stripper.
 31. A system as defined in claim 30,comprising a fired heater unit connected in line with and downstream ofthe heat exchanger, wherein the reboiling of naphtha bottom streamproduct from the naphtha splitter further utilizes the fired heaterunit.
 32. A system as defined in claim 30, wherein the heat exchangerunit is a first heat exchanger unit configured to transfer heat frombottom stream product from the naphtha stripper to bottom stream productfrom the naphtha splitter, the system further comprising: a fired heaterunit positioned to reboil bottom stream product from naphtha stripper; asecond heat exchanger unit positioned to receive additional bottomstream product from the naphtha stripper and additional bottom streamproduct from the naphtha splitter so that the additional bottom streamproduct from the naphtha stripper provides heat energy to the additionalbottom stream product from the naphtha splitter to reboil the additionalbottom stream product from the naphtha splitter; and wherein thereboiling of naphtha bottom stream product from the naphtha splitterfurther utilizes the first and the second heat exchanger units.
 33. Asystem as defined in claim 32, wherein the first and the second heatexchanger units are collectively configured to provide sufficient heatexchange capacity to reboil the bottom stream product from the naphthasplitter without use of a fired heater unit positioned to directlyreboil the bottom stream product from naphtha splitter, the naphthasplitting process section being devoid of a fired heater unit.
 34. Asystem to hydrotreat naphtha feedstocks for provision to a refiningreforming unit, comprising: a naphtha stripping process section directlyintegrated with a naphtha splitting process section to enhance energyefficiency of a naphtha hydrotreating process; a first heat exchangerunit positioned to receive a bottom stream product of heavy naphtha froma naphtha splitter and a bottom stream product from a naphtha stripper,such that the bottom stream product from the naphtha stripper providesheat energy to the bottom stream product from the naphtha splitter; andthe naphtha splitter, the naphtha stripper, and the first heat exchangerunit operably coupled to conduct reboiling of heavy naphtha bottomstream product from the naphtha splitter, the reboiling conductedutilizing naphtha stripper bottom stream product from the naphthastripper; a naphtha hydrotreat reaction process section including areactor unit providing bottom stream product to the naphtha stripper, anaphtha hydrotreat reaction process section comprising a reactorfurnace; a second heat exchanger unit positioned to receive bottomstream product from the reactor unit and additional bottom streamproduct from the naphtha stripper so that the bottom stream product fromthe reactor unit provides heat energy to the additional bottom streamproduct from the naphtha stripper; the reactor unit, the naphthastripper, and the second heat exchanger unit operably coupled to conductreboiling of bottom stream product from the naphtha stripper; wherein abeta ratio of the reactor furnace is at least 3.8.
 35. A system asdefined in claim 34, wherein the heating requirements for the naphthastripping process section, the naphtha splitting process section, andthe naphtha hydrotreat reaction process section are less than 297 onemillion British Thermal Units (MMBTU) per hour.
 36. A system as definedin claim 34, wherein the cooling requirements for the naphtha strippingprocess section, the a naphtha splitting process section, and thenaphtha hydrotreat reaction process section are less than 65 one millionBritish Thermal Units (MMBTU) per hour.
 37. A system as defined in claim34, comprising a fired heater unit connected in line with and downstreamof the second process-to-process heat exchanger, wherein the reboilingof naphtha bottom stream product from the naphtha splitter furtherutilizes the fired heater unit.
 38. A system as defined in claim 37,wherein the load on the fired heater unit is less than 27 one millionBritish Thermal Units (MMBTU) per hour.